This invention relates in general to vehicle tires and in particular, to a method and apparatus to be used in conjunction with curing of vehicle tires.
More specifically, the invention relates to a method and apparatus in which a curing rim having an improved static seal is utilized to support a vehicle tire during a curing operation. The improved curing rim of the invention includes means to introduce an initial pressure to an inner tube to expand a tire into seating relationship on the rim whereby the rim includes means to apply a greater pressure to the exterior of the inner tube to deflate the inner tube and apply a pressure to the tire to maintain it in position during a curing operation. The rim of the invention further includes adjustable means accommodating variable width spacers to permit the rim of the invention to be utilized with tires having a variety of widths.
It is a common process in the prior art to cure vehicle tires which method encompasses the buffing and retreading of used tires in a conventional mold under elevated heat conditions. During a curing operation, the vehicle tire is generally maintained on a curing rim whereby an inner tube within the tire is pressurized to such an extent that the tire is maintained in a pressurized condition to permit proper retreading, buffing and the like. However, the use of an inner tube to maintain proper bias of a vehicle tire during curing presents several disadvantages, particularly in conjunction with the use of very large vehicle tires such as found in land moving equipment and the like.
It has been found that often inner tubes pressurized to support a tire often burst during curing. When such failure occurs, the curing operation of a tire is seriously interferred with and improper curing most likely occurs. Moreover, the inner tube utilized to support large vehicle tires are relatively costly and it becomes very expensive to constantly have to replace these items. Thus, the failure of an inner tube within a tire during a curing operation produces serious detrimental results. For these reasons, it is desirable to provide an improved method and apparatus for supporting a vehicle tire during curing in which the aforementioned problems are alleviated.